Accuracy of a Collagen-Plug Biopsy Site Marking Device Deployed After Stereotactic Core Needle Breast Biopsy

OBJECTIVE: The goal of this study was to compare the accuracy of clip placement of a collagen-plug biopsy marking device with that of the more conventional, previously evaluated metallic tissue-marking clips. SUBJECTS AND METHODS. The placement accuracy of 31 collagen-plug marking devices was compared with the placement accuracy of 43 metallic marker clips deployed at biopsies performed between August 1, 2002, and November 20, 2002. The precision of marker placement was assessed by determining the position of the clip relative to the targeted mammographic lesion. Statistical analysis comparing the distance from the clip to the targeted lesion was performed. RESULTS: Using a two-group Wilcoxon's rank sum test, we found the clip-to-target distances for the collagen-plug central titanium marker were significantly different from the clip-to-target distances of the conventional metallic marker clips (p = 0.04). There were significantly fewer cases in which the clip-to-target distance was 1 cm or greater on at least one mammographic projection with the collagen-plug marker (5/31) than with the conventional metallic marker clip (19/43) (chi-square test, p = 0.02). CONCLUSION: The collagen-plug marking device is an effective alternative to existing marker clips, and use of this device may result in fewer cases in which the marker clip is substantially displaced (> or = 1 cm) away from the actual biopsy site.